1. Field of the Invention
The present invention relates to parts of loom and a loom therewith, the part being made of an alloy suitable for dents of read, a heddle, and the like that slide and contact threads.
2. Description of the Related Art
Conventionally, cloth is woven by a loom in the following manner. A woof thread is inserted among a plurality of warp threads by the power of water (water jet loom) or compressed air (air jet loom). The woof thread is pressed. By repeating these steps, cloth is formed. The cloth is wound as woven cloth by a take-up roll.
A part that pushes a woof thread is called dents of reed. A dent is formed in a thin knife shape. A number of dents are arranged in a comb shape. These dents are secured with a rectangular frame. The resultant structure is referred to as a reed. Warp threads are inserted among the dents of reed and woven. A part that arranges a warp thread is termed a heddle. The heddle has a thread hole at the center position. A number of heddles are arranged in parallel and disposed on the frame. By integrally moving the arranged heddles, the warp threads in the thread holes are vertically reciprocated.
The dents of loom and heddles are in contact with the warp threads and woof threads. Thus, these parts should have wear resistance against the warp threads and woof thread.
In addition, when a water jet loom or an air jet loom is used, the dents of reed and heddles should have excellent corrosion resistance. Thus, as structural materials of dents of loom and heddles, an austenite type stainless material (for example, SUS 301 equivalent to AISI 301) and a martensite type stainless material (for example, SUS 420 J2 equivalent to ISO 683-13 5) have been widely used. In a water jet loom a ferrite type stainless material (for example, SUS 430 equivalent to AISI 430) has been used.
In the following description, it is assumed that the material SUS 301 has been cold-worked. The material SUS 301 is composed of 17% by weight of Cr, 7% by weight of Ni, and balance of Fe. The SUS 301 has a structure of an austenite phase and a martensite phase. The SUS 420 J2 is composed of around 13% by weight of Cr, 0.3% by weight of C, and balance of Fe. The material SUS 420 J2 has a structure of a martensite phase. The material SUS 430 is composed of 18% by weight of Cr and balance of Fe. The material SUS 430 has a structure of a ferrite phase.
In recent years, high speed weaving operations have been required. As the speed of the weaving operation becomes high and an environment of the weaving operation becomes severe, requirements of loom parts such as dents of reed and heddles have become strict. In other words, parts of loom should have excellent wear resistance, corrosion resistance, and resistance to permanent set in fatigue. Under severer conditions, the long service lives of the parts of loom are required.
However, the above-described conventional stainless materials have not sufficient characteristics suitable for the loom parts. For example, the material SUS 301 has relatively good corrosion resistance and resistance to permanent set in fatigue, but has not sufficient wear resistance. Owing to this insufficient wear resistance, loom parts using SUS 301 cause clothes to nap or thread to cut in a relatively early stage of weaving operation. In addition, since the material SUS 301 has high hardness, the press mold for molding the loom parts is worn away early.
On the other hand, although the material SUS 420 J2 has almost good wear resistance and resistance to permanent set in fatigue, it does not have sufficient corrosion resistance. Thus, the material SUS 420 J2 tends to corrode. Occurrence of corrosion shortens the service lives of the parts of loom. In addition, although the material SUS 430 has good corrosion resistance, it does not have sufficient resistance to permanent set in fatigue. Thus, the material SUS 430 causes cloth to grain rise. Although the material SUS 430 has intermediate wear resistance of those of the materials SUS 420 J2 and SUS 301, the wear resistance of the material SUS 430 is not sufficient for a part of loom this is required to have long service life.
Thus, stainless materials that have been used as parts of loom do not have long service lives. In particular, as high speed weaving operation and severe manufacturing environment have been required, short service lives of parts of loom are becoming a problem to be solved.